<label>before</label>
<div class="input-group">
    <input type="text" class="form-control" datepicker-popup="yyyy/MM/dd" ng-model="before" is-open="isBeforeOpen"
           close-text="Close" />
    <span class="input-group-btn">
        <button type="button" class="btn btn-default" ng-click="openBefore($event)">
            <i class="glyphicon glyphicon-calendar"></i>
        </button>
    </span>
</div>
<label>after</label>
<div class="input-group">
    <input type="text" class="form-control" datepicker-popup="yyyy/MM/dd" ng-model="after" is-open="isAfterOpen"
           close-text="Close" />
    <span class="input-group-btn">
        <button type="button" class="btn btn-default" ng-click="openAfter($event)">
            <i class="glyphicon glyphicon-calendar"></i>
        </button>
    </span>
</div>